Edit in JSFiddle

$(function(){
    $('.old-value').text( $('input').val() ); // get the input value
    $('input').val('changed input value'); // set the input value
    $('.click').click(function() {
        $('.old-value').text( $('input').val() );
    });
});
<div class="well">
    <span class="click">get value</span>
    <input type="text" value="input value">
    <span class="old-value"></span>
</div>
.click {
    border-bottom: 1px dashed #555;
    cursor: pointer;
}

External resources loaded into this fiddle: